(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization II International Bureau (10) International Publication Number (43) International Publication Date WO 2014/155387 Al 2 October 2014 (02.10.2014) P O P C T (51) International Patent Classification: KZ, LA, LC, LK, LR, LS, LT, LU, LY, MA, MD, ME, A61P 25/18 (2006.01) A61K 31/554 (2006.01) MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, C07D 417/04 (2006.01) C07D 281/16 (2006.01) OM, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, (21) International Application Number: TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, PCT/IN20 13/000752 ZW. (22) International Filing Date: (84) Designated States (unless otherwise indicated, for every 6 December 2013 (06.12.2013) kind of regional protection available): ARIPO (BW, GH, (25) Filing Language: English GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, SZ, TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, TJ, (26) Publication Language: English TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, DK, (30) Priority Data: EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, 1034/MUM/2013 24 March 2013 (24.03.2013) IN MC, MK, MT, NL, NO, PL, PT, RO, RS, SE, SI, SK, SM, TR), OAPI (BF, BJ, CF, CG, CI, CM, GA, GN, GQ, GW, (72) Inventor; and KM, ML, MR, NE, SN, TD, TG). (71) Applicant : PATEL, Tushar [IN/IN]; Patel Tushar Ma- hendrabhai, 2, Rannapark Society, First Floor, Part-I, Declarations under Rule 4.17 : Ghatlodia Road, Gujarat, Ahmedabad 380 061 (IN). — as to the identity of the inventor (Rule 4.1 7(Ϊ)) (72) Inventor: MUKESH, Gohel; Dr. Mukesh Chhaganlal Go- — as to applicant's entitlement to apply for and be granted a hel, 20, Santoor Bunglows, Near Hira Roopa Party Plot, patent (Rule 4.1 7(H)) Iscon-Bopal Road, Ahmedabad 380058 (IN). — as to the applicant's entitlement to claim the priority of the (81) Designated States (unless otherwise indicated, for every earlier application (Rule 4.1 7(in)) kind of national protection available): AE, AG, AL, AM, Published: AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DK, DM, — with international search report (Art. 21(3)) DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, IL, IN, IR, IS, JP, KE, KG, KN, KP, KR, (54) Title: EXTENDED RELEASE DOSAGE FORMS OF QUETIAPINE SALTS (57) Abstract: The present invention relates to extended release dosage forms of weakly basic drugs. Particularly the present inven tion is related to extended release dosage forms of quetiapine or pharmaceutically acceptable salts thereof. EXTENDED RELEASE DOSAGE FORMS OF QUETIAPINE SALTS FIELD OF THE INVENTION The present invention relates to extended release dosage forms of quetiapine or pharmaceutically acceptable salts thereof. BACKGROUND OF THE INVENTION Quetiapine is chemically known as 2-[2-(4-dibenzo[b,fJ[l,4]thiazepin-ll-yl-l- piperazinyl) ethoxyjethanol. Quetiapine has been employed as an antipsychotic or neuroleptic agent in the treatment of schizophrenia and bipolar mania, due to its antidopaminergic activity, as well as depressive episodes associated with bipolar disorder. As a combined serotonin (5HTz) and dopamine (Di) receptor antagonist, quetiapine, including its fumarate salt, is also known for the effective treatment of psychiatric conditions. Quetiapine is a drug of the dibenzothiazepine class and belongs to a group of drugs known as '"atypical" or second generation antipsychotics which have become increasingly popular alternatives to "typical" antipsychotics. Quetiapine molecule is first described in United States Patent No. 4,879,288 (corresponds to European Patent No. 0240228). Later on many references have been published describing various formulations of quetiapine in which certain drawbacks exist in light of the poor dissolution properties of this medicament and the uncontrolled release profile provided by said formulations. There are many arts describing the modified release or sustained release of extended release dosage form of quetiapine. There are various formulations available, which have been developed with quetiapine. WO2012147100 discloses a pharmaceutical composition of quetiapine, more particularly extended release compositions of quetiapine or its pharmaceutically acceptable salts comprising carboxymethyl ethyl cellulose, a non-gelling, hydrophobic release controlling polymer, and processes for preparing the same. WO2010001413 discloses a formulation comprising quetiapine and a non-gelling controlled- release polymer, as well as one or more excipients. Said formulation further comprises a controlled-release coating. WO20 10082220 describes a sustained release pharmaceutical composition of quetiapine, and process for preparing such composition. More particularly, it relates to sustained release pharmaceutical composition of quetiapine comprising a non- gelling agent and pharmaceutically acceptable excipients. US20090220593 discloses a multiple unit extended release dosage forms of quetiapine for oral administration, wherein each unit comprises a core containing quetiapine a d one or more of pharmaceutically acceptable excipients coated with a rate-controlling coating and process for the preparation thereof. WO2005/041935 describes quetiapine formulations which do not provide a constant or substantially constant level of quetiapine, such that the patient can, at certain time intervals, receive therapeutic amounts of quetiapine exceeding the recommended doses, whereas at other times the amount may be below the therapeutically effective limits. It discloses a novel dosage form of quetiapine and its salts, particularly quetiapine hemifumarate including wax dosage forms, press-coat dosage forms, and sprinkle dosage forms, and other novel dosage forms. The invention also provides sustained release and pulsed release dosage forms of quetiapine and its salts. W01997/45 124 describes the use of matrices with a gelling agent. However, in the latter application, the use of water-soluble active ingredients, such as quetiapine or its pharmaceutically acceptable salts, combined with gelling agents such as hydroxypropyl- methylcelluloses, can give rise to a phenomenon known as dumping in which the release of the active ingredient is delayed, but once initiated the release occurs at very high rates. EP 12 18009 describes the preparation of granules containing quetiapine and a freely or very water-soluble binder for their use in suspensions or solutions. WO2003/039516 describes methods for improving the dissolution of poorly dispersible medicaments, including, for example, quetiapine. The dissolution is improved by means of preparing granules in which a floating agent is added to the medicament. Unfortunately, there is no indication about the release profile of these medicaments in the granulate formulations. US 2007/0244093 describes a controlled release dosage form comprising quetiapine and at least one excipient, exhibiting a dissolution profile such that at 4 hours after combining the dosage form with a dissolution media 50 to 95% of the quetiapine, or the pharmaceutically acceptable salt thereof, is released. Examples 10, 12 and 13 are formulations of quetiapine where stearic acid is used as a lubricant and wherein the tablets may further be coated with ethylcellulose. US 2008/0287418 describes a formulation comprising quetiapine or a pharmaceutically acceptable salt thereof wherein the quetiapine content is about 9.6% to about 10.4% by weight and wherein the formulation comprises about 30% hydroxypropyl methyl cellulose by weight and about 7.2% sodium citrate dehydrate by weight. The formulation further comprises 25.1% lactose monohydrate by weight, about 25.1% microcrystalline cellulose and about 1% magnesium stearate by weight. US 2009/0035370 describes an orally deliverable pharmaceutical dosage form comprising quetiapine and at least one pharmaceutically acceptable excipient, wherein quetiapine is in a form of free base and/or pharmaceutically acceptable salt thereof and comprising a major component in immediate release form and one or more minor components in delayed extended release or delayed pulsed-release form. WO2007/058593 relates to the a method of treating a patient suffering from or susceptible to a mood disorder or an anxiety disorder comprising administering a sustained release pharmaceutical composition comprising a pharmaceutically effective amount of quetiapine, or a pharmaceutically acceptable salt thereof, to the patieiit in need thereof. The compositions claimed display a particular mean Cmax characteristics. The proposed method to obtain controlled release of the active ingredient uses the conventional Methocel R excipients. WO2008/098969 describes a granule for the preparation of pharmaceutical compositions comprising a core that contains quetiapine or pharmaceutically acceptable salt thereof as active ingredient and a binder, and a coating layer comprising a lubricant. It is said that the presence of a lubricant in an amount ranging from 5 to 10 % would be sufficient to achieve me goal of the invention. The application suggests the use of lubricants from the glyceryl behenate, glyceryl palmitostearate and macrogol groups. However there are various problems associated with quetiapine and other weakly basic drugs to provide controlled release or extended release formulations. One of the problems associated with the extended release systems for the weakly basic drug is the difficulty in achieving control over the release profiles. Weakly basic drugs exhibits pH dependent solubility and due to varying the solubility according to pH of environment, i seems very difficult to prepare sustained or extended release dosage form with controlled manner release profile. Particularly the dose dumping may lead to undesired outcomes in terms of sudden increase in the concentration of the active ingredients. Dose dumping is one of the most significant drawbacks of extended-release dosage forms. The most significant event of dose dumping under in vitro conditions is the amount of the active agent released at an earlier time point which may lead to increase in the side effects or adverse events.